Detergent dispenser

ABSTRACT

The invention relates to a detergent dispenser and a washing machine having a detergent dispenser, wherein the detergent dispenser ( 2 ) comprises a dispenser housing ( 4 ), an extractable drawer ( 6 ) arranged in the dispenser housing ( 4 ), and a guiding arrangement provided between the drawer ( 6 ) and the housing ( 4 ) for slidable guiding the drawer ( 6 ) in the housing ( 4 ) along an inserting/withdrawal direction (A), wherein the guiding arrangement comprises at least one drawer guiding device ( 8   a ) and at least one housing guiding device ( 10   a ) adapted to engage with each other, wherein the at least one housing guiding device ( 10   a ) at least partially surrounds the drawer guiding device ( 8   a ) or wherein the at least one drawer guiding device ( 8   a ) at least partially surrounds the housing guiding device ( 10   a ), wherein the at least one drawer guiding device ( 8   a ) and the at least one housing guiding device ( 10   a ) are engaged such that a surface portion ( 12   a ) of the at least one drawer guiding device ( 8   a - b ) is contacting a surface portion of the at least one housing guiding device ( 10   a ) and both surface portions are adapted to slide along each other, and wherein the cross-section of the at least partially surrounded (drawer or housing) guiding device and the mating cross-section of the at least partially surrounding (housing or drawer) guiding device is selected from a partially circular cross-section or a partially ellipse cross-section.

The invention relates to a detergent dispenser for a washing machine anda washing machine comprising such a detergent dispenser.

EP 1 449 951 B2 discloses a washing machine having a detergentdispenser. The detergent dispenser comprises a dispenser housing and anextractable drawer arranged in the housing. According to an embodimentthe drawer comprises slidebars adapted to slide along inner rails of thehousing to slide the drawer in and out of the housing. Two lateralslidebars guide the drawer horizontally and two additional slidebarssupport and guide the drawer vertically.

It is an object of the invention to provide a detergent dispenser and awashing machine having a detergent dispenser which is easy tomanufacture and reliable in use.

The invention is defined in claims 1 and 13, respectively. Particularembodiments are set out in the dependent claims.

According to claim 1, a detergent dispenser comprises a dispenserhousing, an extractable drawer arranged in the dispenser housing and aguiding arrangement provided between the drawer and the housing forslidably guiding the drawer in the housing along a pull-out/push-in(inserting/withdrawal) direction. The guiding arrangement comprises atleast one drawer guiding device and at least one housing guiding deviceadapted to engage with each other, wherein the at least one housingguiding device at least partially surrounds the drawer guiding device orvice versa. The at least one drawer guiding device partially surroundsthe housing guiding device. In particular the guiding arrangementcomprises at least one guiding device pair, wherein one of the (housingor drawer) guiding devices partially surrounds, encompasses or gripsaround the other (drawer or housing) guiding device. For example thedrawer (or housing) guiding device may be a protruding device or elementwhich is partially surrounded by the housing (or drawer) guiding device.

The at least one drawer guiding device and the at least one housingguiding device (the at least one guiding device pair) are engaged suchthat a surface portion of the at least one drawer guiding device iscontacting a surface portion of the corresponding one of the at leastone housing guiding device and both surface portions are adapted toslide along each other. In particular no bearing (for example no ball orroller bearing) is used and/or no auxiliary or additional elementinserted between the mating guiding devices (except the below mentionedfriction-reducing layer or coating). The partially surrounded (housingor drawer) guiding device in combination with the contacting surfaceportions results in ‘smooth’ and safe mating of the guiding devices. Inparticular the interacting and/or contacting and/or overlapping surfaceportions of the mating guiding devices have no edges or sharp angles.The cross-section of the at least partially surrounded (drawer orhousing) guiding device and the mating cross-section of the at leastpartially surrounding (housing or drawer) guiding device is selectedfrom a partially circular cross-section, or a partially ellipsecross-section. As one guiding device partially surrounds the other, areliable connection between the guiding devices is provided andadditionally the (surrounded) guiding device is protected from external‘pollutants’ like e.g. detergent (liquid/powder), water etc. By means ofthe above described guiding arrangement a cost-efficient and easy toproduce guiding of the drawer in the housing is achieved which isreliable and fail-safe in use.

Preferably the surface portion of the at least one drawer guidingdevice, the surface portion of the at least one housing guiding deviceor both surface portions are formed by Teflon or a plastic materialhaving a low coefficient of friction. Thus a user may easily andcomfortably slide the drawer in and out of the housing. In particular nogap or a minimal tolerance gap or clearance is provided between the atleast one drawer guiding device and the at least one housing guidingdevice at the regions where the sliding surfaces are in contact duringthe sliding movement. For example in a cross-section perpendicular tothe movement direction A the hollow profile of the receiving one of theguiding devices and the outer profile of the guiding device that isreceived in the hollow profile are mating with no or only a minimumclearance between each other. Thus it is prevented that dirt or debrisattaches to the surface of the surrounded guiding device, as describedabove.

According to a preferred embodiment the surface portion of the at leastone drawer guiding device, the surface portion of the at least onehousing guiding device or both surface portions are formed by Teflonusing one or more of: (i) a Teflon surface coating, (ii) a bi-injectionforming by providing a plastic material for the bulk of the at least onedrawer and/or housing guiding device and a Teflon material for thesurface portion, or (iii) forming the at least one drawer and/or housingguiding device by Teflon material. All embodiments provide an easy andcomfortable inserting/withdrawing of the drawer as described above.

Preferably the sliding direction is linear such that the at least onedrawer guiding device is adapted to move along a linear direction withrespect to the housing, and wherein the at least one drawer guidingdevice and the at least one housing guiding device are engaged such thatthey provide a mutual form fit acting in a direction perpendicular tothe linear direction. The at least one guiding device pair is engagedwith each other, holds on to each other or is fixed to each other suchthat they cannot be separated perpendicular to the (linear) guiding axisor inserting/withdrawal direction. In particular a one-sided guidingarrangement of the drawer is possible, i.e. one or more drawer/housingguiding device pair(s) may be provided on one side of the drawer.

Alternatively or additionally one ore more drawer/housing guiding devicepair(s) as described above may be provided between a bottom portion ofthe drawer and the housing. I.e. a guiding arrangement may be providedbetween the base of the drawer and the housing.

Preferably the partially circular cross section is at least 300°, 250°,200°, 190° of a full circle or of a full ellipse, such that therespective surrounded guiding device is reliably encompassed and areliable hold structure is provided.

According to a preferred embodiment the guiding arrangement comprises atleast two drawer guiding devices arranged on opposing sides of thedrawer and at least two corresponding housing guiding devices arrangedat the housing. Thus a reliable lateral support is provided for thedrawer, such that tilting of the drawer is reliably prevented duringsliding-in/-out, even when the drawer is pushed /pulled off-center.

Preferred the guiding arrangement comprises at least two drawer guidingdevices arranged on one side of the drawer and at least twocorresponding housing guiding devices. I.e. only two lateraldrawer/housing guiding device pairs may be provided on one side of thedetergent dispenser. Alternatively two lateral housing/drawer guidingdevice pairs may be provided on each side of the detergent dispenser,e.g. four drawer/housing guiding device pairs.

According to an embodiment the at least one drawer guiding device isformed in one-piece with the drawer or alternatively the at least onehousing guiding device is formed in one piece with the housing. Inparticular the material of the respective guiding device and thedrawer/housing are the same, such that they may be manufactured in onestep, e.g. by injection molding. While one guiding device may beprovided in one-piece with the drawer or housing, the other guidingdevice may be attached or fixed to the housing or drawer in a separatestep. Alternatively both guiding devices, i.e. the at least one drawerguiding device and the at least one housing guiding device, are formedin one-piece with the drawer and housing, respectively.

Preferred the at least one drawer guiding device is fixed to the draweror the at least one housing guiding device is fixed to the housing. Thematerial of the drawer/housing and the respective guiding device may bedifferent, e.g. the material of the housing/drawer and guiding device(s)may be adapted individually to the specific requirements of thedetergent dispenser. For example the material of the guiding devices mayhave a low friction coefficient and the drawer material may be resilientagainst detergent or other chemicals. Alternatively the at least onedrawer guiding device is fixed to the drawer and the at least onehousing guiding device is fixed to the housing.

According to an embodiment a clearance is provided between a front edgeof the partially surrounded guiding device and (the rear side of) afront panel of the drawer or a front opening of the housing when thedrawer is fully inserted in the housing. For example when filling indetergent into the drawer some of the detergent may fall on the exposedguiding device (e.g. of the drawer). When the drawer is pushed into thehousing, the detergent on the exposed guiding device is pushed along theguiding device until it falls off at its end (which is at the front edgeof the guiding device), for example into the gap. Thus it is providedthat no debris (detergent) accumulates on the respective guiding device.

Preferably the guiding arrangement is not biased, in particular notbiased in vertical direction. I.e. (sidewise or lateral) contactpressure, e.g. due to spring-biased guiding devices, is prevented. Thusless strain is exerted on the drawer/housing and less abrasion on theguiding devices.

According to an embodiment, the dispenser housing and/or the extractabledrawer is formed as a single-piece or monolithic component. Preferablyin form of a single-injection molded component, wherein in case ofsurface coating with reduced friction preferably co-injection is used.Alternatively the dispenser housing and/or the extractable drawer areformed from two or three shell elements which are connected together toform a combined component.

A washing machine is provided having a detergent dispenser according toany of the above and below described embodiments.

Reference is made in detail to a preferred embodiment of the invention,an example of which is illustrated in the accompanying figures, whichshow:

FIG. 1 a a perspective view of the washing machine with a partiallypulled-out detergent drawer,

FIG. 1 a perspective side view of a detergent dispenser of the washingmachine shown in FIG. 1 a with the detergent drawer of FIG. 1 apartially pulled-out of the housing of the detergent dispenser,

FIG. 2 a perspective side view of the housing of the detergent dispensershown in FIG. 1,

FIG. 3 a perspective side view of the drawer of the detergent dispenserof FIG. 1,

FIG. 4 a sectional front view of the detergent dispenser of FIG. 1,

FIG. 4 a-c details of a guiding arrangement of FIG. 4, and

FIG. 5 a top view of the detergent dispenser of FIG. 1.

An exemplary washing machine 1 is shown in FIG. 1 a in perspective view.The washing machine 1 has an outer housing or cabinet 30. A loadingopening 34 is arranged at the front side of the cabinet 30 forloading/unloading laundry into/out of a drum when a front door 32 of themachine is opened. At the upper front side of the cabinet a controlpanel 36 is arranged having program control elements for receiving auser selection for the washing program and for indicating to the userthe selected program and/or current program states of the machine. Inthis embodiment an exemplary detergent dispenser 2 is arranged at theupper left front side which receives and temporarily stores washingagents filled in by the user. FIG. 1 a shows the detergent dispenser 2opened such that a detergent drawer 6 is partially extracted from ahousing 4 (see FIG. 1) in which the drawer is received when the user hasfully pushed-in the drawer 6.

FIG. 1 shows a perspective side view of the detergent dispenser 2 forthe washing machine shown in FIG. 1 a. The detergent dispenser 2comprises the housing 4 and the drawer 6 which—as shown in FIGS. 1 a and1—is partially extracted or pulled-out from the housing 4 along apush/pull direction A. Three detergent compartments 18 a-c are providedin the drawer 6, e.g. adapted to receive a detergent and softener for awashing operation. A guiding arrangement is provided between the drawer6 and the housing 4 to slidably support the drawer 6 in the housing 4(for sliding the drawer 6 in and out relative to the housing 4). Theguiding arrangement comprises a drawer guiding device 8 a, 8 b on eachside of the drawer and a corresponding housing guiding device 10 a, 10 bat the housing 4. I.e. one pair of lateral guiding devices 8 a, 10 a and8 b, 10 b is provided on each side of the detergent dispenser 2 (FIG.5).

The drawer guiding devices 8 a-b are protruding from the drawer body andare shaped in form of a cylinder having an axis parallel to direction A.Correspondingly the housing guiding devices 10 a-b are formed in form ofa hollow partial-cylinder which is adapted to at least partiallysurround or encompass the respective drawer guiding device 8 a-b.

FIGS. 2 and 3 show perspective side views of the housing 4 and thedrawer 6. The drawer 6 is inserted into the housing 4 via the housingopening 16. As shown in FIG. 3, the drawer guiding devices 8 a-b do notextend along the complete length of the drawer 6. In this embodiment aclearance or gap 20 a-b (FIG. 5) is provided between a front 22 of thedrawer 6 and the guiding device 8 a-b in direction A. The clearanceprovides a predefined extension in direction A from the front region ofthe drawer where no guiding devices 8 a, 8 b are formed.

As can be seen from FIG. 2, the dispenser or drawer housing 4 is formedof two parts. This is a body shell 4 a which—besides the liquidopenings—is open to the front side to receive the drawer 6 and is openat the top side. The open top side is covered by a substantially flatcover shell 4 b which prevents leakage of washing detergents and waterto the outside of the housing 4. Alternatively, the housing may beformed of a single-piece or monolithic body formed for example by blowmolting. The drawer is formed of two shell elements, which are a drawerbase body 6 a (shown in FIGS. 1 and 3) in which or by which the washingagent chambers and the drawer front 22 are formed and a handle panel 6 bwhich is mounted to the basic body at the drawer front 22. The handlepanel 6 b is shown in FIG. 1 a and is removed for illustrative purposesin FIGS. 1 and 3.

FIG. 1 shows the detergent dispenser 2 in a partially extracted position(the normal filling position) when detergent is filled into at least oneof the compartments 18 a-c. It may occur that some detergent is spilled,such that it settles on the (protruding) drawer guiding device 8 a-b.When the drawer 6 is pushed into the housing 4, the spilled detergent ispushed along the drawer guiding device 8 a-b and wiped away into anddownward through the clearance 20 a-b. According to the shown embodimentthe spilled detergent (or any other debris) is removed from the guidingdevice 8 a-b by simply sliding the drawer 6 into the housing 4. Thus anaggregation of debris or detergent on the guiding arrangement isprevented which may affect adversely its function.

FIG. 4 shows a sectional front view of the detergent dispenser 2 ofFIG. 1. FIGS. 4 a-c show details of the guiding arrangement of thedetergent dispenser 2, in particular the arrangement of a pair of ahousing/drawer guiding device 8 a, 10 a. The drawer guiding device 8 acomprises a circular or substantially circular cross-section with aguiding surface 12 a which may comprise Teflon or other low-frictioncoating to minimize friction during inserting (pushing)/withdrawing(pulling). The housing guiding device 10 a comprises a correspondingcircular guiding surface 14 a which is adapted to receive the drawerguiding device 8 a as shown in FIG. 4 c.

As shown in the Figures, the drawer guiding devices 8 a-b are formed inone-piece with the drawer 6 and the housing guiding devices 10 a-b areformed in one-piece with the housing 4, preferably by injection molding.

As shown in FIG. 4 c the drawer/housing guiding devices 8 a, 10 a arefitted or mate to each other such that a minimum gap or no gap isprovided between the respective guiding surfaces 12 a, 14 a. Thus theguiding arrangement is free or substantially free of play.

The housing guiding device 10 a surrounds about 250° of (the circularcross-section of) the drawer guiding device 8 a, in particular surroundsmore than 180° of the drawer guiding device 8 a. Thus the guidingarrangement provides a form-fit in horizontal direction, i.e.perpendicular to slide-in/slide-out direction A.

FIG. 5 shows a top view of the detergent dispenser 2 of FIG. 1 with apartially withdrawn drawer 6. By providing a guiding device pair 8 a, 10a and 8 b, 10 b on each side of the detergent dispenser 2 or drawer 6,which provide a horizontal form-fit, the drawer can be easily andcomfortably withdrawn from (and inserted into) the housing withouthorizontal or vertical tilting relative to the housing 4, even when thedrawer 6 is pulled (or pushed) off-center.

REFERENCE NUMERAL LIST

-   1 washing machine-   2 detergent dispenser-   4 housing-   4 a body shell-   4 b cover shell-   6 drawer-   6 a base body-   6 b handle panel-   8 a-b drawer guiding device-   10 a-b housing guiding device-   12 a-b guiding surface (drawer)-   14 a-b guiding surface (housing)-   16 housing opening-   18 a-c detergent compartment-   20 a-b clearance/gap-   22 drawer front-   30 cabinet-   32 front door-   34 loading opening-   36 control panel-   A inserting/withdrawing direction

1. Detergent dispenser (2) comprising: a dispenser housing (4), anextractable drawer (6) arranged in the dispenser housing (4), and aguiding arrangement provided between the drawer (6) and the housing (4)for slidable guiding the drawer (6) in the housing (4) along aninserting/withdrawal direction (A), wherein the guiding arrangementcomprises at least one drawer guiding device (8 a-b) and at least onehousing guiding device (10 a-b) adapted to engage with each other,wherein the at least one housing guiding device (10 a-b) at leastpartially surrounds the drawer guiding device (8 a-b) or wherein the atleast one drawer guiding device (8 a-b) at least partially surrounds thehousing guiding device (10 a-b), wherein the at least one drawer guidingdevice (8 a-b) and the at least one housing guiding device (10 a-b) areengaged such that a surface portion (12 a-b) of the at least one drawerguiding device (8 a-b) is contacting a surface portion (14 a-b) of theat least one housing guiding device (10 a-b) and both surface portionsare adapted to slide along each other, and wherein the cross-section ofthe at least partially surrounded (drawer or housing) guiding device andthe mating cross-section of the at least partially surrounding (housingor drawer) guiding device is selected from a partially circularcross-section or a partially ellipse cross-section.
 2. Detergentdispenser according to claim 1, wherein the surface portion (12 a-b) ofthe at least one drawer guiding device (8 a-b), the surface portion (14a-b) of the at least one housing guiding device (10 a-b) or both surfaceportions are formed by Teflon or a plastic material having a lowcoefficient of friction.
 3. Detergent dispenser according to claim 1 or2, wherein the surface portion (12 a-b) of the at least one drawerguiding device (8 a-b), the surface portion (14 a-b) of the at least onehousing guiding device (10 a-b) or both surface portions are formed byTeflon using one or more of: a Teflon surface coating, a bi-injectionforming by providing a plastic material for the bulk of the at least onedrawer and/or housing guiding device and a Teflon material for thesurface portion, or forming the at least one drawer and/or housingguiding device by Teflon material.
 4. Detergent dispenser according toclaim 1, 2 or 3, wherein the inserting/withdrawal direction (A) islinear such that the at least one drawer guiding device (8 a-b) is movedalong a linear direction with respect to the housing (4), and whereinthe at least one drawer guiding device (8 a-b) and the at least onehousing guiding device (10 a-b) are engaged such that they provide amutual form fit acting in a direction perpendicular to the lineardirection (A).
 5. Detergent dispenser according to any of the previousclaims, wherein the partially circular cross section is at least 300°,250°, 200°, 190° of a full circle.
 6. Detergent dispenser according toany of the previous claims, wherein the guiding arrangement comprises atleast two drawer guiding devices (8 a-b) arranged on opposing sides ofthe drawer (6) and at least two corresponding housing guiding devices(10 a-b) arranged at the housing (4).
 7. Detergent dispenser accordingto any of the previous claims, wherein the guiding arrangement comprisesat least two drawer guiding devices arranged on one side of the drawerand at least two corresponding housing guiding devices.
 8. Detergentdispenser according to any of the previous claims, wherein the at leastone drawer guiding device (8 a-b) is formed in one-piece with thedrawer, wherein the at least one housing guiding device (10 a-b) isformed in one piece with the housing, or wherein the at least one drawerguiding devices (8 a-b) are formed in one-piece with the drawer and theat least one housing guiding device (10 a-b) is formed in one piece withthe housing.
 9. Detergent dispenser according to any of claims 1 to 7,wherein the at least one drawer guiding device is fixed to the drawer,wherein the at least one housing guiding device is fixed to the housing,or wherein the at least one drawer guiding device is fixed to the drawerand the at least one housing guiding device is fixed to the housing. 10.Detergent dispenser according to any of the previous claims, wherein aclearance (20 a-b) is provided between the at least partially surroundedguiding device and a front (22) of the drawer or a front opening (16) ofthe housing when the drawer (6) is fully inserted in the housing (4).11. Detergent dispenser according to any of the previous claims, whereinthe guiding arrangement is not biased, in particular not biased invertical direction.
 12. Detergent dispenser according to any of theclaims 1 to 7 and 9 to 11, wherein the dispenser housing (4), theextractable drawer (6), or the dispenser housing (4) and the extractabledrawer (6) are formed as a single-piece or monolithic component or areformed as a two-part or two-shell joint component (4 a, 4 b; 6 a, 6 b).13. Detergent dispenser according to any of the previous claims, whereinno bearing, ball bearing or roller bearing is arranged between themating guiding devices or wherein no auxiliary element or additionalelement is inserted between the mating guiding devices.
 14. Washingmachine (1) having a detergent dispenser (2) according to any of theprevious claims.